JPS5824656B2 - Hydraulic clutch check valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a check valve for a hydraulic clutch that prevents clutch drag and engagement due to residual oil remaining in the hydraulic operating chamber of the hydraulic clutch.

Leaf spring type check valves are known as this type of check valve, but in order to overcome the centrifugal force of residual oil, the opening force of the leaf spring type must be set large enough to open even at the maximum rotation of the clutch. be.

However, if this setting is made, the check valve will not close until the pressure in the hydraulic chamber reaches a high enough pressure to close the leaf spring type check valve when hydraulic oil is supplied to the hydraulic chamber, prolonging clutch drag. This causes problems such as accelerated wear of the clutch friction plates, and also causes problems in which hydraulic oil continues to leak until the check valve closes, resulting in a drop in oil pressure in the hydraulic system.

In order to improve this problem, if the hydraulic pump is made larger, it becomes a load after the clutch is engaged, leading to a decrease in overall efficiency, and a large amount of hydraulic oil is suddenly supplied into the hydraulic chamber to close the check valve once. As a result, there was a problem in that the oil pressure rose rapidly in the hydraulic operation chamber, causing a large engagement shock.

These problems are most noticeable at low rotation speeds when centrifugal force is less active.

The purpose of the present invention is to eliminate the above-mentioned problems and obtain a check valve that opens and closes reliably.The present invention aims to solve these problems and provide a check valve that opens and closes reliably. To provide a check valve.

To explain this with reference to the illustrated embodiment, 1 is a drive shaft, 2 is a driven shaft, and 3 is a hydraulic clutch, and the clutch 3 includes a clutch cylinder 4 connected to the drive shaft 1, and a clutch hub connected to the driven shaft 2. 5 and.

Drive plates 6a and driven plates 6b are arranged alternately between the cylinder 4 and the hub 5.
a clutch piston 7 fitted into the clutch cylinder 4 to engage the friction material 6; and a clutch piston 7 that is defined by the clutch piston 7 and the clutch cylinder 4 and provided on the drive shaft 1. It is formed of a hydraulic working chamber 9 connected to the hydraulic pressure supply path 8 and a return spring 10 for returning the clutch piston 7, and a return spring 10 is provided in the hydraulic working chamber 9 to protrude from the clutch piston 7 so as to come into contact with the friction material 6. An annular groove 1b is formed on the inner surface of the provided annular bulge 7a, and the inner surface of the groove 7b forms a seat surface 11 facing radially outward in the hydraulic operating chamber 9. A spring 13 of a leaf spring type check valve 14 is provided with a leak hole 12 that communicates the hydraulic chamber 9 with the atmosphere, and a leaf spring 13 is provided to open and close the leak hole 12. The leaf spring 13 is fixed to the leaf spring 13 and moved radially outward by its own spring force to open the leak hole 12, and furthermore, the movable part side receives a centrifugal force and receives a force in the direction of assisting the opening force of the leaf spring 13. Mass given 15
A leaf spring 1 is provided in the hydraulic operating chamber 9.
Stopper 1 that restricts movement in the opening direction due to centrifugal force in Step 3
6 is provided so as to abut near the free end of the leaf spring 13.

Note that the mass 15 is the leaf spring 13 in the illustration.
The splinter was formed with a separate weight, but this can be done by enlarging the free end of one splinter as shown in Figure 3a, or by using a third splinter.
The stopper 16 may be made by bending the free end as shown in the figure, and the stopper 16 is formed by a pin installed in the wall in the figure, but it is formed by the wall of the radially inner surface of the hydraulic chamber 9. Alternatively, the check valve 14 may be formed by bending the free end as shown in FIG. Further, although the leaf spring 13 is attached using rivets in the illustrated embodiment, it may also be attached using screws.

Since the present invention is constructed as described above, when the clutch 3 is rotating, the check valve '14 has its own valve of the leaf spring 13.

The valve-opening force based on the ring force and the valve-opening force acting on the mass due to the centrifugal force are acting, and line pressure is added to the hydraulic chamber 9.
When the hydraulic oil is supplied to the hydraulic chamber 9, centrifugal force acts on the hydraulic oil in the hydraulic chamber 9, which causes the leaf spring 13 to generate a valve-closing force. Centrifugal force.

If the mass 15 is selected so that the valve closing force based on The check valve 14 closes immediately when the pressure is reached, and by selecting the opening force based on the spring force of the leaf spring 13, the clutch piston 7 can be operated quickly even when the hydraulic pressure in the hydraulic chamber is low, and the line pressure If it disappears, leaf spring 1
The valve opening force due to the self-spring force acting on the leaf spring 3 and the centrifugal force acting on the mass 15 is caused by the residual oil.
Is it greater than the valve closing force acting on 3? Therefore, the leak hole 12 is opened by the force of the leaf spring, and as described above, according to the present invention, the leaf spring 13 receives centrifugal force and is given a force in a direction that promotes the valve opening force due to its own spring force. The leak hole 12 is formed in the seat surface facing in the radial direction of the hydraulic chamber so that the direction of the centrifugal force acting on the mass 15 coincides with the valve opening direction of the leaf spring 13. At the same time, the leaf spring 13 faces the leak hole 12 and moves radially outward by its own spring force to open. Opening and closing can be done smoothly.

In addition, when a stopper 16 is provided in the hydraulic chamber to restrict movement of the leaf spring 13 in the opening direction due to centrifugal force, the stopper 16 is connected to the leaf spring 13 and the leak hole 12.
Since the gap between the leaf spring and
The leaf spring 13 tries to close due to the negative pressure generated on the leaf spring 1 side.
This has the effect of reducing the centrifugal force exerted on the fixing rivets or screws in No. 3.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; Fig. 1 is a longitudinal cross-sectional view, Fig. 2 is a front view of the main part of Fig. 1, and Fig. 3 shows another embodiment of the leaf spring. A is a plan view, and b is a side view. 1... Drive shaft, 2... Driven shaft, total...
...Hydraulic clutch, 9...Hydraulic operating chamber, 11
...Sheet surface, 12 ...Leak hole, 1
3...Leaf spring, 14...Check valve, 15...Mass, 16...
·stopper.

Claims (1)

[Scope of Claims] 1. In a hydraulic clutch that engages and disengages a drive shaft and a driven shaft, in which a leaf spring type check valve is provided in a hydraulic chamber, the leak hole of the check valve is located outside the hydraulic chamber in the radial direction. A leaf spring is formed on the seat surface facing the leak hole, and is fixed to the wall so as to move radially outward of the hydraulic chamber by its own spring force to open the leak hole, and centrifugal force is applied to the movable part. A check valve for a hydraulic clutch, characterized in that it is provided with a mass that applies a force in a direction that promotes the valve opening force of a spring. 2. The check valve for a hydraulic clutch according to claim 1, wherein a stopper is provided in the hydraulic chamber to restrict movement of the leaf spring in the opening direction due to centrifugal force.